The present invention relates to technology useful for a semiconductor device manufacturing method which includes the step of transporting, for example, a container housing stacked semiconductor wafers.
WO 2004/089784 concerns a wafer protective sheet which is inserted between semiconductor wafers to protect the semiconductor wafers when the semiconductor wafers are stacked and housed in a container. It discloses that when a plurality of semiconductor wafers are put in a container and transported with a lid on the container, a protective sheet of synthetic resin which has many projected and recessed parts on the front and back surfaces is interposed between wafers to protect the semiconductor wafers against vibrations during transportation.
Japanese Unexamined Patent Application Publication No. Hei 08 (1996)-330407 discloses a cushion material for transportation of semiconductor wafers which is a porous resin sheet.